quiz 4

Question 1

name: 4 main regions of the brain + func.

Answer 1

1. brainstem
   ⤷ connects spinal cord to brain
   ⤷ integration of reflexes + necessary for survival
2. cerebellum
   ⤷ lump on inferior anterior part of brain
   ⤷ controls locomotion, balance, posture
3. diencephalon
   ⤷ connects brainstem to cerebrum
   ⤷ coordinates output of pituitary
   ⤷ has: thalamus, epithalamus, hypothalamus, subthalamus
4. cerebrum
   ⤷ 2 large hemispheres
   ⤷ controls concious thought (higher order thinking)

Question 2

name: protection for brain (3)

Answer 2

1. cranial bones (8 bones)
2. cranial meninges
   ⤷ pia
   ⤷ arachnoid
   ⤷ dura mater (meningeal layer + periosteal layer)
3. cerebrospinal fluid

Question 3

order: layers of protection for brain in order from deep to superficial (8)

Answer 3

1. pia mater
2. subarachnoid space
3. arachnoid mater
4. subdural space
5. meningeal dura (dura mater layer)
6. dural venous sinous
7. periosteal dura (dura mater layer)
8. cranial bone

Question 4

explain: types of meninges

Answer 4

• dura mater = dense irreg. CT = very strong
• at a groove: meningeal dura pulls away from periosteal
  ⤷ makes a space (dural venous sinous) that carries venous blood
• arachnoid mater = thin layer of fibrous mem.
  ⤷ web like struc.
• pia mater = very thin mem.
  ⤷ adheres to cerebrum + spinal cord
• space in between arachnoid mater and pia mater = subarachnoid space (fills w/ CSF)

Question 5

explain: types of ventricles

Answer 5

• lateral ventricles (2 ventricles)
  ⤷ begin as 2 large C shaped cav. on sides of corpus callosum
  ⤷ primary site of CSF prod. (ependymal cells)
• interventricular foramen
  ⤷ space from lat. vent. to 3rd vent.
• third vent.
  ⤷ surrounds diencephalon
• cerebral aqueduct
  ⤷ from midbrain to 4th vent.
  ⤷ CSF runs through it
• fourth vent.
  ⤷ pons + medulla oblongata come in contact w/ cerebellum
  ⤷ has 3 apertures that allow CSF to enter subarachnoid space

Question 6

explain: CSF as protection

Answer 6

• serum-like fluid that lacks prot. but has nutrients (glucose)
• bathes + protects brain and spinal cord
• synthesized in choroid plexus in lat. vent.

Question 7

order: path of CSF flow

Answer 7

1. choroid plexus (ependymal cells)
2. lateral ventricles
3. interventricular space
4. 3rd ventricle
5. cerebral aqueduct
6. 4th ventricles
7. apertures (1 median, 2 lateral) + central canal
8. subarachnoid space
9. arachnoid granulation
10. superior sagittal sinus

Question 8

name: parts of brainstem (3)

Answer 8

1. medulla oblongata
2. pons
3. midbrain

Question 9

explain: medulla oblongata + location

Answer 9

• in brainstem (bottom part)
• transmits ascending + descending impulses between brain and spinal cord
• has pyramids and olives

Question 10

explain: roles of pyramids and olives + location

Answer 10

• in brainstem -> medulla oblongata
• pyramids = descending nerve tracts (white matter)
  ⤷ motor tracts = controls skeletal muscle
  ⤷ imp. for vital reflexes (heart rate, blood psi, respiratory sys., swallowing, coughing, sneezing)
• olives = nuclei involved in balance, coordination, modulation of sound
  ⤷ nuclei of cranial nerves V, VI, IX, X, XI, XII
  ⤷ redirects info to cerebellum

Question 11

explain: pons + location

Answer 11

• in brainstem (middle part)
• ascending + descending nerve tracts from cerebrum to spinal cord
• sleep center + respira. center
  ⤷ REM sleep
• anterior = Pontine nuclei: comm. between cerebrum and cerebellum
• posterior = nuclei of cranial nerves V, VI, VII , VIII

Question 12

explain: midbrain + location

Answer 12

• in brainstem (top part under diencephalon)
• nuclei of cranial nerves III, IV, V
• tectum - 4 nuclei (mounds)
  ⤷ 2 superior colliculi (vis.)
  ⤷ 2 inferior colliculi (aud.) (startling noise reflex)
• has cerebellar peduncles

Question 13

explain: cerebellar peduncles + location

Answer 13

• in brainstem -> midbrain
• bundles of axons
• basically a nerve tract
• white matter connections to cerebellum
• superior = midbrain to cerebellum
• middle = pons to cerebellum
• inferior = medulla oblongata to cerebellum

Question 14

explain: reticular formation + location

Answer 14

• in brainstem
• group of nuclei scattered throughout brainstem (reticular cloud)
• controls cyclic sys.
  ⤷ ex. sleep-wake specifically conciousness

Question 15

explain: cerebellum

Answer 15

• comms. w/ other regions of CNS
  ⤷ vis peduncles (brainstem parts)
• 3 regions:
  1. flocculonodular lobe: balance (from vis. and tactile info)
  2. vermis: anterior = gross motor coor., posterior - fine motor
  3. cerebellar (lat.) hemisphere = fine motor

Question 16

explain: lecture 12 case study (missing cerebellum)

Answer 16

• could still survive
• however could not fine tune complex motions
• other portions of brain may have taken over resp. of cerebellum
• dev. of skills (ex. walking, talking) took longer and still not completely fine tuned

Question 17

explain: diencephalon

Answer 17

• between brainstem and cerebrum
• 4 main components
  ⤷ thalamus
  ⤷ subthalamus
  ⤷ epithalamus
  ⤷ hypothalamus

Question 18

explain: thalamus + location

Answer 18

• in diencephalon (top oval-ish flaps)
• lat. parts connected by interthalamic adhesion
  ⤷ all surrounded by third vent.
• receives most sensory info.
  ⤷ except smell
  ⤷ projects to cerebral cortex

Question 19

explain: subthalamus + location

Answer 19

• in diencephalon
  ⤷ inferior to thalamus
• ascending + descending nerve tracts
  ⤷ many nerves bc pass through subthalamus to reach thalamus (sensory info)
• subthalamic nucleus controls motor func.

Question 20

explain: epithalamus + location

Answer 20

• in diencephalon
  ⤷ posterior + superior to thalamus
• 2 parts
  1. habenula: emo./visceral resp. to odour
  2. pineal gland: secretes melatonin
  ⤷ may influence puberty and menopause

**habenula above pineal gland, pineal gland = pinecone/small bean shaped thing

Question 21

explain: hypothalamus + location

Answer 21

• in diencephalon
  ⤷ most inferior part
  ⤷ very deep
• has stalk
  ⤷ infundibulum: connects hypothalamus to pituitary
• links nervous + endocrine sys.
• many clusters of nuclei (12+)

Question 22

explain: cerebrum

Answer 22

• outer: cerebral cortex (gray matter)
• in between: cerebral medullar (white matter)
• higher level processing
  ⤷ intellectual func.

Question 23

explain: cerebral cortex + location

Answer 23

• outer part of cerebrum
• gyri = outward bumps
• sulci = inward depressions
• fissures = deeper depressions

Question 24

name: types of fissures in cerebral cortex (5)

Answer 24

• longitudinal fissure = separates LR hemis.
• central sulcus = separates frontal + parietal lobes
• parietaloccipital sulcus = separates parietal and occipital lobes
• lateral fissure/lateral cerebral sulcus = separates temporal from frontal + parietal lobes
• transverse fissure = separates cerebrum from cerebellum

Question 25

name: lobes of brain + func.

Answer 25

FPOT (fm, ps, ta, o)
⤷ frontal motor
⤷ parietal somatosensory
⤷ temporal auditory
⤷ occipital vision

1. frontal
   - motor func.
   - mood + aggression
2. parietal
   ⤷ touch, pressure, blood pH
   ⤷ most sensory info except smell, taste, vision, hearing
3. occipital
   ⤷ reception + integration of visual info
4. temporal
   ⤷ olfactory, auditory
   ⤷ memory

Question 26

explain: pre and post central gyrus

Answer 26

• on either side of central sulcus
• pre = primary motor cortex (skeletal musc.)
• post = primary somatosensory cortex (no vis., aud., smell)

Question 27

explain: cerebral medulla + location

Answer 27

• inner part of cerebrum
• nerve tracts connect cortex to other parts of CNS
• association, commissural, and projection fibers

Question 28

explain: func. of fibers in cerebral medulla (3)

Answer 28

1. association fibers
   ⤷ connect areas cerebral cortex w/in same hemis.
2. commissural
   ⤷ connect cerebral hemis.
   ⤷ makes up corpus callosum
3. projection fibers
   ⤷ connects cerebrum to other parts of brain + spinal cord